textproduct: Rapid City

KEY MESSAGES

- Very hot temperatures will continue through much of this week, with record high temps possible and dangerous heat.

- Near-critical to critical fire weather conditions will continue this week.

DISCUSSION

(This Evening Through Sunday) Issued at 228 PM MDT Sun Jul 12 2026

Extreme upper ridge continues to sit across the northern Plains through the central Rockies. At the surface...low pressure across Wyoming is keeping winds at 10kt or less across most of the NE WY plains. As expected, temps are in the triple digits. The hottest temps nearby are across far northern Campbell County through southeastern MT into Butte County, in the 105-110F range. Unofficially, the warmest temperature in the CWA so far is 111F at a RAWS station in northern Campbell County. Not much change to the pattern is expected through the next several days, with highs at or above 100F across the plains each day through at least Thursday. Therefore, have extended the Heat Advisory through then. Contemplated upgrading part of the CWA to a Extreme Heat Warning based on local criteria (100F+ apparent temp for four days or longer) but will keep it simple w/ the Advisory since apparent temps become marginal past Tuesday as drier air moves in from the west, dropping dewpoints 10-15F. This will lower apparent temps across the majority of the CWA to near or below warning thresholds. Regardless, it's splitting hairs since it will still feel hot. Medium range models show some relief coming next weekend or early next week as a cold front finally pushes through.

AVIATION

(For the 18Z TAFS Through 18Z Monday) Issued At 1140 AM MDT Sun Jul 12 2026

Expect VFR conditions through the forecast period.

Gusty south/southeast winds will develop again this afternoon, strengthening tonight over northeast Wyoming due to a tightening surface gradient.

FIRE WEATHER

Issued At 228 PM MDT Sun Jul 12 2026

Strong high pressure over the region for much of the week will bring very hot temperatures, along with dry air and breezy winds. Very low humidity and breezy winds will continue through this afternoon and early evening, bringing critical fire weather conditions from the northeastern Wyoming to the far western South Dakota plains. On Monday and Tuesday across much of the western South Dakota plains, winds will again become breezy with gusts up to 35 mph and combine with the very low humidity of 15% or less to support critical fire weather conditions. In addition, poor humidity recoveries are expected each night. A Red Flag Warning has been extended until Tuesday evening. Will continue to monitor the potential for critical fire weather conditions for the second half of the week.

UNR WATCHES/WARNINGS/ADVISORIES

SD...Heat Advisory until 9 PM MDT /10 PM CDT/ Thursday for SDZ001-002- 012>014-025>027-030>032-041>044-046-047-049-072>078. Red Flag Warning until 9 PM MDT Tuesday for SDZ322>332. WY...Heat Advisory until 9 PM MDT Thursday for WYZ054>056-058>060. Red Flag Warning until 9 PM MDT this evening for WYZ314>317.